prepare system state observer+feedback

fuzzers/wcet_qemu_sys/src/bin/showmap.rs

@@ -1,5 +1,6 @@
 //! A singlethreaded QEMU fuzzer that can auto-restart.
 
+use wcet_qemu_sys::system_trace::QemuSysStateObserver;
 use wcet_qemu_sys::worst::QemuHashMapObserver;
 use wcet_qemu_sys::{
     worst::{DumpMapFeedback,DummyFeedback},
@@ -328,7 +329,7 @@ fn fuzz(
             QemuSysSnapshotHelper::new(),
             QemuSystemStateHelper::with_instrumentation_filter(system_state_filter,curr_tcb_pointer.try_into().unwrap(),task_queue_addr.try_into().unwrap())
         ),
-        tuple_list!(edges_observer,clock_observer),
+        tuple_list!(edges_observer,clock_observer,QemuSysStateObserver::new()),
         &mut fuzzer,
         &mut state,
         &mut mgr,

fuzzers/wcet_qemu_sys/src/system_trace.rs

@@ -1,3 +1,10 @@
+use libafl::events::EventFirer;
+use libafl::state::HasClientPerfMonitor;
+use libafl::feedbacks::Feedback;
+use libafl::bolts::HasLen;
+use libafl::bolts::tuples::Named;
+use libafl::Error;
+use libafl::observers::Observer;
 use crate::freertos::rtos_struct::*;
 use crate::freertos;
 use hashbrown::HashMap;
@@ -5,27 +12,36 @@ use libafl::{executors::ExitKind, inputs::Input, observers::ObserversTuple, stat
 use serde::{Deserialize, Serialize};
 
 use libafl_qemu::{
+    emu,
     emu::Emulator,
     executor::QemuExecutor,
     helper::{QemuHelper, QemuHelperTuple, QemuInstrumentationFilter},
 };
 
+//============================= Datatypes
+
+/// Info Dump from Qemu
+pub type SysState = (u64,freertos::TCB_t,HashMap<u32,freertos::rtos_struct>);
+
+/// Refined information about the states an execution transitioned between
 #[derive(Debug, Default, Serialize, Deserialize)]
 pub struct QemuSystemStateMetadata {
-    pub rtos_states: Vec<(freertos::TCB_t,HashMap<u32,freertos::rtos_struct>)>,
 }
 
 impl QemuSystemStateMetadata {
     #[must_use]
     pub fn new() -> Self {
-        Self {
-            rtos_states: Vec::new(),
-        }
+        Self {}
     }
 }
 
 libafl::impl_serdeany!(QemuSystemStateMetadata);
 
+
+//============================= Qemu Helper
+static mut CURRENT_SYSSTATE_VEC: Vec<SysState> = vec![];
+
+/// A Qemu Helper with reads FreeRTOS specific structs from Qemu whenever certain syscalls occur
 #[derive(Debug)]
 pub struct QemuSystemStateHelper {
     filter: QemuInstrumentationFilter,
@@ -65,6 +81,8 @@ where
         OT: ObserversTuple<I, S>,
         QT: QemuHelperTuple<I, S>,
     {
+        // emu::Emulator{_private: ()}.set_gen_block_hook(test_gen_hook);
+        executor.hook_block_generation(gen_not_exec_block_hook::<I, QT, S>);
         executor.hook_block_execution(exec_syscall_hook::<I, QT, S>);
     }
 }
@@ -84,26 +102,135 @@ where
     if !h.must_instrument(pc) {
         return;
     }
-    if state.metadata().get::<QemuSystemStateMetadata>().is_none() {
-        state.add_metadata(QemuSystemStateMetadata::new());
-    }
-    let meta = state
-        .metadata_mut()
-        .get_mut::<QemuSystemStateMetadata>()
-        .unwrap();
+    let current_clock = emulator.get_ticks();
     let curr_tcb_addr : freertos::void_ptr = freertos::emu_lookup::lookup(emulator, h.tcb_addr);
-    // println!("Current TCB addr: {:x}",curr_tcb_addr);
     let current_tcb : freertos::TCB_t = freertos::emu_lookup::lookup(emulator,curr_tcb_addr);
-    println!("{:?}",current_tcb);
-    println!("{}", std::str::from_utf8(&current_tcb.pcTaskName).unwrap());
-    let mut result_tup : (freertos::TCB_t,HashMap<u32,freertos::rtos_struct>) = (current_tcb, HashMap::with_capacity(5));
+    let mut result_tup : SysState = (current_clock,current_tcb, HashMap::with_capacity(5));
     for i in 0..4 {
         let target : u32= (std::mem::size_of::<freertos::List_t>()*i).try_into().unwrap();
         let ready_list : freertos::List_t = freertos::emu_lookup::lookup(emulator, h.ready_queues+target);
         let a : freertos::rtos_struct = List_struct(ready_list);
-        result_tup.1.insert(target,a);
-        // println!("{:?}",ready_list);
-        // println!("Prio: {} Number: {} first {:x}",i,ready_list.uxNumberOfItems, ready_list.pxIndex);
+        result_tup.2.insert(target,a);
     }
-    meta.rtos_states.push(result_tup);
+
+    unsafe { CURRENT_SYSSTATE_VEC.push(result_tup); }
 }
+
+extern "C" fn test_gen_hook(pc: u64) -> u64 {
+    u32::MAX as u64
+}
+
+pub fn gen_not_exec_block_hook<I, QT, S>(
+    _emulator: &Emulator,
+    helpers: &mut QT,
+    _state: &mut S,
+    pc: u64,
+)
+-> Option<u64> where
+    S: HasMetadata,
+    I: Input,
+    QT: QemuHelperTuple<I, S>,
+{
+    let h = helpers.match_first_type::<QemuSystemStateHelper>().expect("QemuSystemHelper not found in helper tupel");
+    if !h.must_instrument(pc) {
+        None
+    } else {Some(1)}
+}
+
+//============================= Observer
+
+/// The QemuSysState Observer retrieves the SysState
+/// that will get updated by the target.
+#[derive(Serialize, Deserialize, Debug, Default)]
+#[allow(clippy::unsafe_derive_deserialize)]
+pub struct QemuSysStateObserver
+{
+    last_run: Vec<SysState>,
+    name: String,
+}
+
+impl<I, S> Observer<I, S> for QemuSysStateObserver
+{
+    #[inline]
+    fn pre_exec(&mut self, _state: &mut S, _input: &I) -> Result<(), Error> {
+        unsafe {CURRENT_SYSSTATE_VEC.clear(); }
+        Ok(())
+    }
+
+    #[inline]
+    fn post_exec(&mut self, _state: &mut S, _input: &I) -> Result<(), Error> {
+        unsafe {self.last_run.append(&mut CURRENT_SYSSTATE_VEC);}
+        Ok(())
+    }
+}
+
+impl Named for QemuSysStateObserver
+{
+    #[inline]
+    fn name(&self) -> &str {
+        self.name.as_str()
+    }
+}
+
+impl HasLen for QemuSysStateObserver
+{
+    #[inline]
+    fn len(&self) -> usize {
+        self.last_run.len()
+    }
+}
+
+impl QemuSysStateObserver {
+    pub fn new() -> Self {
+        Self{last_run: vec![], name: "sysstate".to_string()}
+    }
+}
+
+//============================= Feedback
+
+/// A Feedback reporting interesting System-State Transitions
+#[derive(Serialize, Deserialize, Clone, Debug)]
+pub struct SysStateFeedback
+{
+}
+
+impl<I, S> Feedback<I, S> for SysStateFeedback
+where
+    I: Input,
+    S: HasClientPerfMonitor,
+{
+    fn is_interesting<EM, OT>(
+        &mut self,
+        _state: &mut S,
+        _manager: &mut EM,
+        _input: &I,
+        _observers: &OT,
+        _exit_kind: &ExitKind,
+    ) -> Result<bool, Error>
+    where
+        EM: EventFirer<I>,
+        OT: ObserversTuple<I, S>,
+    {
+        let observer = _observers.match_name::<QemuSysStateObserver>("sysstate")
+            .expect("QemuSysStateObserver not found");
+        // Do Stuff
+        Ok(false)
+    }
+}
+
+impl Named for SysStateFeedback
+{
+    #[inline]
+    fn name(&self) -> &str {
+        "sysstate"
+    }
+}
+
+impl SysStateFeedback
+{
+    /// Creates a new [`SysStateFeedback`]
+    #[must_use]
+    pub fn new() -> Self {
+        Self {}
+    }
+}